clk: ep93xx: add DT support for Cirrus EP93xx

Rewrite EP93xx clock driver located in arch/arm/mach-ep93xx/clock.c
trying to do everything the device tree way:

- provide clock acces via of
- drop clk_hw_register_clkdev
- drop init code and use module_auxiliary_driver

Co-developed-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

drivers/clk/Kconfig

@@ -218,6 +218,14 @@ config COMMON_CLK_EN7523
 	  This driver provides the fixed clocks and gates present on Airoha
 	  ARM silicon.
 
+config COMMON_CLK_EP93XX
+	tristate "Clock driver for Cirrus Logic ep93xx SoC"
+	depends on ARCH_EP93XX || COMPILE_TEST
+	select AUXILIARY_BUS
+	select REGMAP_MMIO
+	help
+	  This driver supports the SoC clocks on the Cirrus Logic ep93xx.
+
 config COMMON_CLK_FSL_FLEXSPI
 	tristate "Clock driver for FlexSPI on Layerscape SoCs"
 	depends on ARCH_LAYERSCAPE || COMPILE_TEST

drivers/clk/Makefile

@@ -30,6 +30,7 @@ obj-$(CONFIG_COMMON_CLK_CDCE706)	+= clk-cdce706.o
 obj-$(CONFIG_COMMON_CLK_CDCE925)	+= clk-cdce925.o
 obj-$(CONFIG_ARCH_CLPS711X)		+= clk-clps711x.o
 obj-$(CONFIG_COMMON_CLK_CS2000_CP)	+= clk-cs2000-cp.o
+obj-$(CONFIG_COMMON_CLK_EP93XX)		+= clk-ep93xx.o
 obj-$(CONFIG_ARCH_SPARX5)		+= clk-sparx5.o
 obj-$(CONFIG_COMMON_CLK_EN7523)		+= clk-en7523.o
 obj-$(CONFIG_COMMON_CLK_FIXED_MMIO)	+= clk-fixed-mmio.o